1. Field of the Invention
The present invention relates to a waterproof and/or water-resistant camera, and more precisely, it relates to a waterproof and/or water-resistant camera having a photographing lens barrel which is movable relative to a camera body.
2. Description of the Related Art
Recently, water-resistant cameras which do not permit rain, spoon-drift (spray) or the water from a stream to permeate therethrough, or waterproof cameras which can take a picture even in shallow water have been available on the market. There have been attempts to realize a waterproof and/or water-resistant zoom lens camera. In the attempts, one of the most significant problems to be solved is a water-tight connection between the movable photographing lens barrel and the immovable camera body. To this end, it is known to provide an O-ring (annular seal member)in a space defined between the photographing lens barrel which is mounted to the camera body so as to retractably and relatively move through an opening formed in the front wall of the camera body and the inner peripheral edge of the front wall of the camera body which defines the opening. It is necessary to provide an air breathing passage which connects the inside and the outside of the camera body in order to absorb a change in volume of the space in which the photographing lens barrel moves, thereby to absorb a change in operational force of the photographing lens barrel, thus resulting in smooth zooming and focusing operations.
To satisfy both the requirements of the air breathing and watertightening watertightness, it is necessary to provide an air-permeable and water-impermeable filter in the air breathing passage.
To reduce the passage resistance of the air breathing passage, preferably, the air-permeable and water-impermeable filter is provided to be exposed on the outer surface of the camera body, however this increases the possibility that the air-permeable and water-impermeable filter may be damaged, soiled or clogged, thus resulting in a deterioration of the filter.
Also, the exposure of the filter has an adverse effect on the appearance of the camera.
To solve the problems mentioned above, it is possible to provide a protection cover which covers the air-permeable and water-impermeable filter, however this increases the possibility that water may remain in a space defined between the air-permeable and water-impermeable filter and the protection cover, thus resulting in a decrease of the air-permeability of the air-permeable and water-impermeable filter.
FIG. 20 shows an example of an annular seal member 23 provided in the space defined between the photographing lens barrel 12 and the opening 19a formed in a stationary lens barrel 19 of the camera body. In FIG. 20, the annular seal member 23 is compressed or contracted by the inner wall (fastening portion) 24 of the stationary lens barrel 19 to bring the seal member 23 into press contact with the outer periphery of the photographing lens barrel 12 in a watertight fashion. In FIG. 20, numeral 53 designates a cam ring, 54 a cam groove, and 48 a stationary ring, respectively.
In the arrangement shown in FIG. 20, when the center axis O of the annular fastening portion 24 is identical to the center axis O' of the photographing lens barrel 12 which is inserted in the opening 19a, as shown in FIG. 21, no problem is raised. However, if the center axis O' of the photographing lens barrel 12 is deviated from the center axis O of the annular fastening portion 24, the inner periphery A of the annular seal member 23 is irregularly deformed with respect to the outer periphery B thereof, as shown in FIG. 22. The irregular deformation leads to a failure to watertight connection or an increase of a frictional resistance against the slide movement of the photographing lens barrel 12.